Sunday, September 11, 2005

Health Effects Among WTC Recovery Site Workers

BrooklynDodger returns to 9/11 and the World Trade Center site.

This paper comes from Johns Hopkins, adding yet another team of investigators.

Repeating previous posts, exposures were well below OSHA limits for everything, except for welders who were almost all in compliance but had scattered exposures at or near the OSHA limit.

Employees were truck drivers, laborers, carpenters, and heavy equipment operators. No welders [ironworkers] or firefighters. The text is unclear on the subjects arrival date at the site. Tests were conducted 3 months into the event, some employees appeared to have been there from the early days, but clearly after the initial collapse and cloud of large particle dust.

“Among the 183 workers who Participated in this study, 52% reported nasal congestion, 43% reported sore throat, and 44% reported experiencing a hoarse throat while working at the site. Of the 119 workers who began working at the site with no previous history of lower respiratory symptoms, 34% developed a new cough, 24% reported new phlegm production, and 19% reported new wheeze.”

The investigators had no data on pre- and post- PFT’s. Those with symptoms had lower PFT’s than those without.

Another independent data point showing effects well below the OSHA PEL’s.


Respiratory effects of inhalation exposure among workers during the clean-up effort at the World Trade Center disaster site.

Herbstman JB, Frank R, Schwab M, Williams DL, Samet JM, Breysse PN, Geyh AS.

Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.

During December 2001 we conducted a field study of 183 clean-up and recovery workers at the World Trade Center (WTC) disaster site to assess respiratory health effects potentially resulting from their work at the site. On site, we administered a respiratory health questionnaire designed to assess upper respiratory symptoms and lower respiratory symptoms, including cough, phlegm, and wheeze, as well as indices of exposure, including number of days worked at the site and job category. Spirometry was conducted for 175 workers. Sixty-five percent of the workers surveyed arrived at the site without lower respiratory symptoms. Of this group, 34% developed cough, 24% developed phlegm, and 19% developed wheeze. Prevalence rates of these symptoms were related to the number of days spent working at the WTC, but not job category. The mean percentage predicted FEV(1) and FVC were 6% and 5% lower, respectively, for workers who developed new lower respiratory symptoms compared to those who remained symptom free. While the development of new wheeze suggested the presence of airway obstruction, the near-normal distribution of age-adjusted FEV(1)/FVC ratios suggested that the degree of obstruction was mild. The prevalence rates of upper airway symptoms (nasal congestion, sore throat, hoarse throat) exceeded those of lower respiratory symptoms, however, it was not determined whether symptoms pre-dated arrival at the WTC site.

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